Key information relevant to the recruitment process for the
overall study, such as dates of the recruitment period and locations

All participants had to be at low risk of acquiring human immunodeficiency virus (HIV) infection, and had to meet a number of laboratory criteria. They could not have received treatment for hepatitis C virus infection in the 3 months prior to enrollment and must not anticipate to begin treatment with in 1 year after enrollment.

Pre-Assignment Details

Significant events and approaches for the overall study
following participant enrollment, but prior to group assignment

Participants were to be administered MRKAd5 HIV-1 gag 1x10^10 vp/dose (V520) on Day 1, Week 4, and Week 26.

Per a letter dated 30-Aug-2005 all sites were notified that due to recruitment challenges enrollment would be halted as of 01-Oct-2005. Consequently, no participants were enrolled in the group MRKAd5 HIV-1 gag 1x10^10 vp/dose.

Explanation of how the number of participants for analysis was determined.
Includes whether analysis was per protocol, intention to treat, or another method.
Also provides relevant details such as imputation technique, as appropriate.

Participants were to be administered MRKAd5 HIV-1 gag 1x10^10 vp/dose (V520) on Day 1, Week 4, and Week 26.

Per a letter dated 30-Aug-2005 all sites were notified that due to recruitment challenges enrollment would be halted as of 01-Oct-2005. Consequently, no participants were enrolled in the group MRKAd5 HIV-1 gag 1x10^10 vp/dose.

Number of Participants With Vaccine-related Clinical (Systemic and Injection-site), and Laboratory Adverse Events (AE) [ Time Frame: up to Week 78 (52 weeks after boost injection) for systemic AEs, 29 days after any dose for laboratory AEs, and 5 days after any dose for injection-site AEs ]

Measure Type

Primary

Measure Title

Number of Participants With Vaccine-related Clinical (Systemic and Injection-site), and Laboratory Adverse Events (AE)

Measure Description

Serious and non serious clinical (systemic and injection-site AEs), and laboratory AEs were collected. Systemic and laboratory AEs reflect any unfavorable & unintended change in the structure, function, or chemistry of the body. Injection-site AEs include any swelling, redness, pain or tenderness at the injection site.

Vaccine-related AEs are those determined by the investigator to be possibly, probably, or definitely related to the administration of the vaccine.

Time Frame

up to Week 78 (52 weeks after boost injection) for systemic AEs, 29 days after any dose for laboratory AEs, and 5 days after any dose for injection-site AEs

Safety Issue

Yes

Population Description

Explanation of how the number of participants for analysis was determined.
Includes whether analysis was per protocol, intention to treat, or another method.
Also provides relevant details such as imputation technique, as appropriate.

Number of Participants With Vaccine-related Clinical (Systemic and Injection-site), and Laboratory Adverse Events (AE)
[units: Participants]

With non-serious vaccine-related (VR) clinical AEs

5

1

---With non-serious VR systemic AEs

3

1

---With non-serious VR injection-site AEs

3

1

With serious VR clinical AEs

0

0

---With serious VR systemic AEs

0

0

---With serious VR injection-site AEs

0

0

With non-serious VR laboratory AEs

2

0

With serious VR laboratory AEs

0

0

discontinued due to non-serious VR clinical AE

0

0

discontinued due to serious VR clinical AE

0

0

discontinued due to VR non-serious laboratory AE

0

0

discontinued due to VR serious laboratory AE

0

0

No statistical analysis provided for Number of Participants With Vaccine-related Clinical (Systemic and Injection-site), and Laboratory Adverse Events (AE)

2. Secondary:

Number of Participants With Systemic and Laboratory Adverse Events (AE) [ Time Frame: up to Week 260 (234 weeks after boost injection) for systemic AEs, 29 days after any dose for laboratory AEs, and 5 days after any dose for injection-site AEs ]

Measure Type

Secondary

Measure Title

Number of Participants With Systemic and Laboratory Adverse Events (AE)

Measure Description

Adverse experiences collected include serious and non serious systemic AEs, injection-site AEs, and laboratory AEs. Systemic and laboratory AEs include any unfavorable & unintended change in the structure, function, or chemistry of the body. Injection-site AEs include any swelling, redness, pain or tenderness at the injection site. All injection site AEs were collected up to 5 days after any vaccine dose.

Time Frame

up to Week 260 (234 weeks after boost injection) for systemic AEs, 29 days after any dose for laboratory AEs, and 5 days after any dose for injection-site AEs

Safety Issue

Yes

Population Description

Explanation of how the number of participants for analysis was determined.
Includes whether analysis was per protocol, intention to treat, or another method.
Also provides relevant details such as imputation technique, as appropriate.

No immunogenicity analyses were performed because the results from a previous study, V520-023 (NCT00095576), which used the same vaccine as the one used in this study (NCT00857311) proved it was not efficacious.

Time Frame

Week 30 (4 weeks after boost injection)

Safety Issue

No

Population Description

Explanation of how the number of participants for analysis was determined.
Includes whether analysis was per protocol, intention to treat, or another method.
Also provides relevant details such as imputation technique, as appropriate.

Limitations of the study, such as early termination leading to small numbers of participants
analyzed and technical problems with measurement leading to unreliable or uninterpretable data

An interim analysis of a related study, V520 Protocol 023 (NCT00095576), showed that the MRKAd5 vaccine used in Protocol 022 (NCT00857311) was not efficacious; therefore, only a high level summary of the safety data was performed.